Our overall objective is to study the role of hormones in the control of biochemical processes in developing fetal tissues. We have developed methods for the extraction and HPL chromatography of peptides from various areas of the pituitary and brain which allows us to proceed with the isolation of molecules of mol wt 300 - 30,000. These peptides will be tested to determine whether they stimulate corticosteroid synthesis in fetal adrenal cells in monolayer culture. The evaluation of this biologic activity is done by measuring stimulation of endogenous production (no substrate) or exogenous production (3H progesterone or unlabeled progesterone as substrate) of corticosteroids. We will also evaluate the stimulation of C19 steroid production (dehydroisoandrosterone sulfate, androstenedione and testosterone) and adrenal growth. We are continuing our studies on the formation, metabolism and mode of action of prostaglandins and thromboxanes in fetal tissues. We are also continuing our research on the hormonal control of hemoglobin synthesis in human and calf fetal liver cells in culture. Particular emphasis will be paid to the elucidation of the structure of a new fetal calf hemoglobin F1 which is a post-transcriptional transformation product of the alpha chain of Fo, the normal calf fetal liver hemoglobin. The hormonal control of this transformation by erythropoietin and other hormones will be investigated.